In-vivo bleeding may occur due to different diseases in the body. Bleeding in the gastrointestinal (GI) tract may occur in various locations along the GI tract, and this may indicate different pathologies present at those locations. For example, bleeding in the esophagus may be due to esophagitis or due to ruptures in varices in the esophagus. An ulcer in the stomach, as well as an ulcer in the duodenum, may cause bleeding. And, in the lower digestive tract, colorectal cancer may cause occult bleeding. Therefore, early detection of bleeding along the GI tract may be crucial for better treatment of many patients.
An in-vivo device that may be used to detect in-vivo bleeding is described in International Patent Application Publication No. WO 2010/086859. For example, as shown in FIGS. 1A-1B of International Patent Application Publication No. WO 2010/086859, such an in-vivo device comprises a housing having a gap, through which in-vivo fluids may enter and exit. On one side of the gap is at least one illumination source, and on the other side of the gap, facing the illumination source, is a light detector. The illumination source may illuminate the in-vivo fluids which freely flow through the gap, and the light passing through the fluids may then be detected by the light detector. Following experiments with such a device, it was realized that tissue and bubbles occasionally enter the gap and either stay inside the gap or block the gap for substantial periods of time. When tissue and/or bubbles are stuck inside the gap such that they are positioned between the illumination source and the light detector, readings by the light detector are disrupted, and thus true indication of presence of blood within in-vivo fluids is not possible.
There is, therefore, a need to add to such in-vivo devices (as the device described in International Patent Application Publication No. WO 2010/086859) new means in order to prevent tissue and/or bubbles from entering the gap between the illumination source and the light detector, while enabling free flow of in-vivo fluids in and out of the gap. Such new means may ensure accurate and reliable readings of the light that passes through the in-vivo fluids, which freely flow in and out of the gap, without any disruption by tissue and/or bubbles.